1 // SPDX-License-Identifier: GPL-2.0
2
3 #ifndef _LINUX_MM_SLOT_H
4 #define _LINUX_MM_SLOT_H
5
6 #include <linux/hashtable.h>
7 #include <linux/slab.h>
8
9 /*
10 * struct mm_slot - hash lookup from mm to mm_slot
11 * @hash: link to the mm_slots hash list
12 * @mm_node: link into the mm_slots list
13 * @mm: the mm that this information is valid for
14 */
15 struct mm_slot {
16 struct hlist_node hash;
17 struct list_head mm_node;
18 struct mm_struct *mm;
19 };
20
21 #define mm_slot_entry(ptr, type, member) \
22 container_of(ptr, type, member)
23
mm_slot_alloc(struct kmem_cache * cache)24 static inline void *mm_slot_alloc(struct kmem_cache *cache)
25 {
26 if (!cache) /* initialization failed */
27 return NULL;
28 return kmem_cache_zalloc(cache, GFP_KERNEL);
29 }
30
mm_slot_free(struct kmem_cache * cache,void * objp)31 static inline void mm_slot_free(struct kmem_cache *cache, void *objp)
32 {
33 kmem_cache_free(cache, objp);
34 }
35
36 #define mm_slot_lookup(_hashtable, _mm) \
37 ({ \
38 struct mm_slot *tmp_slot, *mm_slot = NULL; \
39 \
40 hash_for_each_possible(_hashtable, tmp_slot, hash, (unsigned long)_mm) \
41 if (_mm == tmp_slot->mm) { \
42 mm_slot = tmp_slot; \
43 break; \
44 } \
45 \
46 mm_slot; \
47 })
48
49 #define mm_slot_insert(_hashtable, _mm, _mm_slot) \
50 ({ \
51 _mm_slot->mm = _mm; \
52 hash_add(_hashtable, &_mm_slot->hash, (unsigned long)_mm); \
53 })
54
55 #endif /* _LINUX_MM_SLOT_H */
56